/*  $OpenBSD: vasprintf.c,v 1.19 2015/12/28 22:08:18 mmcc Exp $ */

/*
 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "local.h"

int
vasprintf(char **str, const char *fmt, va_list ap)
{
    int ret;
    FILE f;
    struct __sfileext fext;
    unsigned char *_base;
    unsigned char buf[128];

    _FILEEXT_SETUP(&f, &fext);
    f._file = -1;
    f._flags = __SWR | __SSTR | __SALC;
    f._bf._base = f._p = buf;
    f._bf._size = f._w = 127;/* Leave room for the NUL */
    ret = __vfprintf(&f, fmt, ap);
    if (ret == -1)
        goto err;
    *f._p = '\0';
    _base = malloc(ret + 1);
    if (_base == NULL)
        goto err;
    memcpy(_base, f._bf._base, ret + 1);
    *str = (char *)_base;
    return (ret);

err:
    *str = NULL;
    errno = ENOMEM;
    return (-1);
}
